Work operations are often performed on multiple layers of sheet-type work material, for example, in the mass production of garments, pattern pieces are usually cut from multiple layers of fabric spread one-on-top-of-the-other on a support surface. To facilitate clean accurate cuts, the layers of work material, often referred to as a lay, must be adequately held in place during the performance of a cutting operation. Failure to do so can result in movement of the fabric layers relative to one another, detrimentally affecting the performance of the cutting operation.
Generally, pattern pieces are cut from the lay using what is referred to as a cutter table. The support surface is mounted on the cutter table and is typically permeable, and often moveable relative to the table. The permeable support surface is in part comprised of a plurality of slats linked together and extending transversely of the frame.
A moveable cutter head traverses the support surface, cutting pattern pieces from the layers of material in response to commands issued from a controller. To eliminate any undesired movement of the layers of work material during the performance of the cutting operation, vacuum is sometimes used to draw and hold the work material against the support surface. A difficulty sometimes encountered with the above described cutter tables is that vacuum is often lost through the lateral edge sections of the support surface resulting in inadequate retention of the work material, detrimentally affecting the quality of the cut pattern pieces.
In an effort to seal the lateral edge sections of the support surface end blocks formed from a compressible, closed-cell material, such as foam, have been attached to the ends of the slats. However, over time the foam would suffer permanent deformation destroying the integrity of the seal.
Based on the foregoing, it is the general object of the present invention to provide an apparatus for retaining multiple layers of sheet material against a support surface that overcomes the drawbacks of prior art apparatus for sealing lateral edge sections of a permeable support surface.
It is a more specific object of the present invention to provide an apparatus to adequately seal the lateral edge sections of a conveyorized support surface.